It is very common today, when disciplining children, to use what is known as a "time out" when the child has misbehaved. The time out is a period of time where the child is removed from a situation and required to sit quietly. Timing mechanisms, or clock timers, can be used to measure the length of the time out period.
Timers are well known in the art. Such timers, upon expiration of a desired length of time, typically actuate a bell, buzzer or other audible signal in order to communicate to an individual the expiration of the time period.
These timers are not visually oriented and are not designed with children in mind.